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arXiv · 1003.0303

Non-uniformity of a planar polarizer as a reason of spin-transfer induced vortex oscillations at zero field

A. V. Khvalkovskiy·J. Grollier·N. Locatelli·Ya. V. Gorbunov·K. A. Zvezdin·V. Cros
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Abstract

We discuss a possible mechanism of the spin-transfer induced oscillations of a vortex in the free layer of spin-valve nanostructures, in which the polarizer layer has a planar magnetization. We demonstrate that if such planar polarizer is essentially non-uniform, steady gyrotropic vortex motion with large amplitude can be excited. The best excitation efficiency is obtained for a circular magnetization distribution in the polarizer. In this configuration, the conditions for the onset of the oscillations depend on the vortex chirality but not on the direction of its core.

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A. V. Khvalkovskiy, J. Grollier, N. Locatelli, Ya. V. Gorbunov, K. A. Zvezdin, V. Cros. 2010-03-01. Non-uniformity of a planar polarizer as a reason of spin-transfer induced vortex oscillations at zero field. https://doi.org/10.1063/1.3441405

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